Details

Autor(en) / Beteiligte

• Stern, Michelle A.
• Flint, Lorraine E.
• Flint, Alan L.
• Knowles, Noah
• Wright, Scott A.

Titel

The Future of Sediment Transport and Streamflow Under a Changing Climate and the Implications for Long‐Term Resilience of the San Francisco Bay‐Delta

Ist Teil von

• Water resources research, 2020-09, Vol.56 (9), p.n/a

Ort / Verlag

Washington: Blackwell Publishing Ltd

Erscheinungsjahr

2020

Link zum Volltext

Quelle

Wiley Blackwell Single Titles

Beschreibungen/Notizen

• Sedimentation and turbidity have effects on habitat suitability in the San Francisco Bay‐Delta (Bay‐Delta), concerning key species in the bay as well as the ability of the delta marshes to keep pace with sea level rise. A daily rainfall runoff and transport model of the Sacramento River Basin of northern California was developed to simulate streamflow and suspended sediment transport to the Bay‐Delta for the next century (water years, WY2010–2099). The model was calibrated to historical streamflow and sediment data and applied using 10 Global Climate Models with two representative concentration pathways (RCP) each for WY1980–2099 from the IPCC 5th Assessment Report. Results indicate average increases in peak streamflow of +58% and +66% for the RCP 4.5 and 8.5 ensembles, respectively, by mid‐century and +62 and +96% by end‐of‐century. Sediment loads increased by +39% and +69% by end‐of‐century. Suspended sediment concentrations (SSC) increased on average by +4.6% and +6.7% for RCP 4.5 and 8.5, respectively, by end‐of‐century. Individual scenario results varied, and statistically significant increasing trends of sediment loads to the Bay‐Delta were found for the RCP 4.5 and 8.5 ensembles and five individual scenarios. Increased suspended sediment loads may have negative effects such as contaminant transport but also have positive effects that help protect against sea level rise, increase turbidity and fish habitat, and sustain wetland habitats in the Bay‐Delta. Plain Language Summary The health of the San Francisco Bay‐Delta depends on a sediment supply that has been recently declining. Future climate scenarios were run through a model to determine changes in streamflow and sediment transport. Results from the model showed increases in large flow events and sediment transport over the next century. Increased sediment supply can help buffer wetland habitats against the deleterious effects of sea level rise with benefits to native fishes. Key Points Snowpack below the major reservoirs is projected to decrease dramatically as air temperature increases 1.6–5.3 degrees C by end‐of‐century Peak streamflow increases by 62% and 96% by end‐of‐century for moderate‐ and high‐emission scenarios, respectively Sediment transport increases by 39% and 69% by end‐of‐century for moderate‐ and high‐emission scenarios, respectively